Signed-off-by: Andrei Gherzan <andrei.gherzan@huawei.com>

README.md from docs is now main meta-ohos readme;
adr moved to docs subdirectory

Signed-off-by: Robert Drab <robert.drab@huawei.com>

Leveraging existing BSP base in Yocto meta-layers

Signed-off-by: Robert Drab <robert.drab@huawei.com>